not 蓝绿, but a few pts you can use

1) go to Travelocity, check under Cruise - by destination (Europe, Med, Greece, Turkey, whatever the dropdown menu has), would be the easiest if you dont have a clue about cruiselines.
Or, check it by ships - those that sail in Europe in Summer - RCCL, Princess, Celebrity, Holland America, are the so-called Mass Market lines. The first 3 would suit you better than the last 1.
Prices are all there, before Taxes. You can do a dummy booking to see the tax portion.
You also need to factor in $10 a day for tipping (service personnel on the ship - it is considered part of the total costs, and is really majority part of the wages earned by the service personnel are tips, so please pay.)

2) It goes without saying, DIY excursions would be cheaper than ship-offered excursions. However, you need to pay attn on the time constraint - if the time is too tight, I would join the ship excursion, because missing the boat is no joke!
Transportation between Port and Town in Europe, often involves 2 hours one-way. Keep that in mind. Unless you are cruising Turkey/Turkey. Train has a fixed schedule that you need to account for.

3) One-way car ental is extremely expensive in Europe. In fact, rental is expensive, so does gasoline, about 4 times more than here in many places. Taking train or discount airlines flights would be better bet, esp you have time constraint.

4) Like BlueGreen said, a few sites are very useful for your planning - Foders, Tripadvisor, even Rick Steve's. Forget about Lonely Planet - that is for budget-minded tourists. You obviously would spend money to get more quality time than wasting your time for getting cheaper alternatives.

The above are off the top of my head. Later.